A Time-dependent Analysis for Quasi- One-dimensional Nozzle Flows with Vibrational and Chemical Nonequilibrium

A new technique is presented for the numerical solution of quasi-one-dimensional, vibrational and chemical nonequilibrium nozzle flows including nonequilibrium conditions both upstream and downstream of the throat. This new technique is a timedependent analysis which entails the explicite finite-difference solution of the quasi-one-dimensional unsteady flow equations in steps of time, starting with assumed initial distributions throughout the nozzle. The steady-state solution is approached at large values of time. A virtue of the present time-dependent analysis is its simplicity, which prevails from its initial physical formulation to the successful receipt of numerical results. Also, the present solution yields the transient as well as the steadystate nonequilibrium nozzle flows. To exemplify the present analysis, results are given for several cases of vibrational and chemical nonequilibrium expansions through nozzles. U. S. NAVAL ORDNANCE LABORATORY White Oak, Maryland